New research suggests that the problem with being obese is not simply having too much fat; it’s that your body fat, when in excess, loses its normal functionality.
Fat in normal amounts serves a useful purpose in the body. Fat plays an essential role in many vital bodily processes like the immune response, the regulation of insulin sensitivity, and maintenance of body temperature. You need a modest amount of fat for good health, but like anything, too much of a good thing can be bad.
New research suggests that the negative health effects of obesity are not simply caused by having too much body fat but from the decline in its ability to respond to changes, or in other words, its plasticity.
In a review published in the journal Cell on February 3rd, 2022, researchers argue that as fat declines in plasticity due to aging and obesity, it loses its ability to respond to bodily cues. In the current model of this phenomenon, the rapid growth of adipose tissue outpaces its blood supply, depriving the fat cells of oxygen and causing the accumulation of cells that no longer divide. This leads to insulin resistance, inflammation, and cell death accompanied by the uncontrolled spill of lipids from these cells. It is this loss of functionality of fat tissue and the biological impacts that has on your body, that the researchers say lead to diabetes, heart disease, and the other metabolic conditions and negative consequences of being severely overweight.
“The central role of adipose tissue dysfunction in disease and the incredible plasticity of fat tissue supports the promise of modulating fat tissue phenotypes for therapeutic purposes,” write the authors, led by Claudio J. Villanueva from the College of Life Sciences/David Geffen School of Medicine and Patrick Seale from Perelman School of Medicine at the University of Pennsylvania. “Many questions and opportunities for future discovery remain, which will yield new insights into adipose tissue biology and hopefully lead to improved therapies for human disease.”